Combination contact and terminal for electric switches



Aug. 2.1, 1945. E. N* JAcoBl 2,382,996

COMBINATION CONTACT AND TERMINAL FOR ELECTRIC `SWITCHFS Filed July 19,1944 Ill Patented Aug. 2l, 1945 PATENT t oFFlcE COMBINATION CONTACT ANDTERMINAL FOR ELECTRIC SWITCHES Edward N. Jacobi, Milwaukee, Wis.,assis-nor to Briggs 8a Stratton Corporation, Milwaukee, Wis., acorporation of Delaware Application July 19, 1944, Serial No. 545,627

Claims.

This invention `relates to electric switches and refers particularly tosmall automotive switches which are generally, though not necessarily,actuated by key controlled lock mechanisms. Switches of this type areillustrated in Patents Nos. 1,842,451 and 1,912,982, issued to E. N.Jacobi. January 26, .1932 and June 6, i933, respectively.

While the invention broadly concerns switches 'of this type, it hasparticularreference to the wire terminals andstationary contactsthereof. One of the features of these switches is that the switchmechanism is 'mountedin the inner end portion .of a cylindrical lockbody or casing adapted to besecured to a panel by a clamping nutthreaded .and the ,attachment of the wires still lie fully -within thecircumference of the lock body or casing so that the clamping nut may befreely applied or removed .after the .wires have been secured inposition. This, of course, is a decided advantage vin that itfacilitates the installation of the switches. `B y virtue of `thisconstruction the vattachment of the wires may be effected undercircumstances considerably more convenient than if they had to'beconnected after the switch was mounted in its position of use. I

Another object of this invention is to provide a wire terminal .of thecharacter described which not only provides .animproved manner of secur--ing the wire leads to the stationary contact members of the switch, butalso serves to secure the stationary contacts in position on theterminal In view of the relatively small size of switches of `this ,typeand the consequently small travel of the movable contactor the heads ofthe stationary contact members must necessarily be small to insure theproper electrical clearance. Still .these contact members should haveenlarged heads to hold the members against being pulled out of theterminal head. As a result, the Shanks of the stationary contactmembers, which protrude through the terminal head, are of limited diam-(ci. zoo-iss) ent invention to obviate this disadvantage through theprovision of means not limited by the diameter of the head on thecontact member for gripping the wire. s 5 With the above and otherobjects in view which will appear as the description proceeds, thisinvention resides in the novel construction, combination and arrangementof parts substantially as hereinafter described and more particularlystood that such changes in the precise embodiment of the hereindlsclosedinvention may be made as come within the scope of the claims.

The accompanying drawing illustrates one complete example of thephysical embodiment of the invention constructed according to the bestmode so far devised foi-,the practical application of the principlesthereof, and in which:

Figure 1 is a side4 view of an electric switch embodying this invention,a part thereof being broken away and in section;

Figure 2. is an exploded perspective view illustrating the various partsof the combination stationary contact and wire terminal;

Figure 3 `isi-an enlarged longitudinal sectional view through theterminal illustrating the same in its completely assembled state; and

Figure 4 is a view illustrating the manner in which the terminals areclinched to effect permanent securement of the contacts and wires.

Referring now particularly'to the accompanying drawing in which likenumerals indicate like parts, the numeral i designates the casing orbody oi a lock switch within which the switch mechanism indicatedgenerally by the numeral 6 is mounted to be `actuated by a rotatabletumbler controlled cylinder 'i upon the insertion of a proper key 8.

The front end 0 of the casing is'i'langed to pro- 40 videa' shoulderwhich bears against the front face of the mounting panel (not shown) andthus f cooperates with a clamping nut Iii to mount the casing or body onthe panel. The nut I0 is adapted to be passed over the inner rear end cfthe casing or body.

The switch mechanism comprises a movable contactor Il connected with thelock cylinder 'l in any conventional manner to be rotated to and from aposition bridging a pair of stationary contacts i2. The stationarycontacts are mounted on an insulated terminal head i3 which is securedin and closes the open rear end of the casing or body.

The two stationary contacts, which are ideneter. It is therefore anotherobject of the prestical, are provided by the heads I4 of headedcydeflned by the appended claims, it being underlindrical pins orcontact members I5. The shank of each of these members is tubular andprojects through a hole I 6 in the terminal head. 'Ihe inner end of thishole is counterbored to receive the head I 4 so that the contact surfacerises but slightly above the inner face of the terminal head. The headsI4 also secure the pins or contact members I5 against being pulled outof the terminal head.

Telescoped over the tubular shank of each of the pins or contact membersI5 is a sleeve I1. One end of this sleeve bears rrly against the outerface of the insulated terminal head and its opposite end portionprojects a substantial distance beyond the pin or contact member I 5.Inserted into each assembled sleeve and pin is an insulated wire I8, theinsulation having been removed from the extreme end portion of the wirewhich enters the tubular shank of the pin or contact member I5, whilethe insulation extends into the sleeve I1.

Sleeve I I may be counterbored to a larger diameter in order to takethicker insulation diameter of Wire I8. Sleeve I'I may also be reducedby turning to a smaller diameter at the neck 20, so that the metal atthis point may be corrugated properly to produce a rm clinch and an Aintimate Contact with the wire.

The assembled sleeves, pins and wires are transversely deformed by beingclinched between complementary dies I9 of an arbor press, as shown inFigure 4. In this manner a localized portion 20 of each terminalassembly is deformed from its normal round transverse shape into an ovalshape thus effecting a mutual interlocking relationship which iirmlylocks the parts together and secures the contact members or pins 5 inposition on the terminal head.

In the clinching operation caremust be taken that the sleeve bearssolidly against the terminal head, and to insurev a solid grip the endsof the sleeves are preferably beveled to provide sharp edges whichrbiteinto the terminal head during the clinching operation. The outer ends ofthe contact members or pins I5 are also preferably beveled to providesharp edges to bite into the ends of the insulation on the wires.

The outermost ends of the sleeves, which are also beveled and have sharpedges, are clinched inwardly around their entire perimeters as at 2| togrip the insulation and hold the same against shifting.

From the foregoing description, taken in connection with theaccompanying drawing, it will be readily apparent to those skilled inthe art that this invention provides a simple but highly effectiveterminal construction for small electric switches and that it provides astrong, solid connection between the wire and stationary contact of theswitch without in anywise interfering with the passage of the clampingnut onto and oil' of the casing or body. Thus it is possible to attachadequate lengths of wire to the switch at the factory and therebyeliminate the difculties attending the attachment of wires after aswitch of this type is mounted in place.

What I claim as my invention is:

1. A combination contact and wire terminal for electric switchescomprising: an insulated terminal head having a hole therethrough; aheaded contact member having an elongated tubular shank received in thehole and projecting beyond the terminal head to provide a wire terminal,the head on the Contact member holding said Contact member against beingpulled through the terminal head; a wire lead having its end portionreceived in the tubular shank; a sleeve fitted over the shank of thecontact member and bearing iirmly against the insulated terminal` head;and said sleeve and tubular shank being transversely clinched to theextent that the wire within the shank of the contact is deformed andsecured to the contact member.

2. In an electric switch: an insulated terminal head having a holetherethrough; a contact member having a tubular shank projecting throughsaid hole; means for limiting endwise movement of the contact member inone direction; a wire lead having its end received in the tubular shank;and a sleeve iitted over the shank of the contact member and bearingrmly against the terminal head; said sleeve, shank and wire beingtransversely clinched into a deformed cross sectional shape whereby saidparts are iirmly secured against movement with respect to each otherwith the sleeve bearing against the terminal head to secure the contactmember in place, and a good electrical connection is established betweenthe contact member and the wire.

3. In an electrical switch: an insulated terminal head having a holetherethrough with a counterbore opening to one face; a headed contactmember having a ltubular cylindrical shank projecting through said holewith its head disposed in the counterbore; a metal sleeve telescopedover the tubular shank of the contact member and bearing rmly againstthe insulated head; and a. wire having its end portion received in thetubular shank, said sleeve, tubular shank and wire having portionsthereof transversely deformed into interiitting, substantially ovalshaped sections so that said parts are secured against relative movementand the contact member is held assembled with the terminal head.

4; In an electric switch: a substantially cylindrical body within whichthe switch mechanism is located, said body having an externally threadedportion and a shoulder; a clamping nut passed over the inner end of thebody and threaded on said threaded portion to cooperate with theshoulder in mounting the switch on a panel; an insulated terminal headclosing the inner end of the body, said terminal head having spacedholes therethrough; stationary contact members having tubular shanksprojecting through said holes but with all parts thereof lying wellwithin the circumference of the cylindrical body; means to preventpulling the contact members out through said holes, the inner ends ofthe contact members providing the stationary contacts of the switch;wire leads having bare end portions received in the tubular shanks ofthe stationary contact members; and sleeves telescoped over said shanksof the contact members and bearing rmly against the outer face of theterminal head, said sleeves, tubular shanks and wires having portionsthereof transversely clinched into mutually interlocking condition tosecure said parts together and iix the contact members to the terminalhead with all portions of the assemblies lying well within thecircumference of the switch body so that the nut may be applied andremoved after the wires are secured in place.

5. A combination stationary contact and terminal comprising: aninsulated terminal head having a hole therethrough; a tubular pin memberreceived in the hole; ahead on one end of said pin member engaging theterminal head at one side thereof to limit movement of the pin memberaxially in o'ne direction; a metal sleeve telescope onto the tubular pinmember with one end bearing firmly against the other side 01' theinsulated head and its other end portion projecting beyond the pinmember; an insulated Wire having a bared end portion disposed within thetubular pin member with its insulation entering the metal sleeve; saidsleeve. tubular pin member and wire being transversely deformed at a.localized area to clinch said parts into mutually interlockingrelationship and secure the pin member to the terminal head, and theouter extremity of the sleeve being clinched inwardb1 to grip theinsulation of the wire.

EDWARD N. JACOBI.

